backend/Musify.Application/PlayLists/GetPlayListsByUserId.cs

@@ -24,7 +24,7 @@ namespace Musify.Application.PlayLists
                 .AsNoTracking()
                 .Where(p => p.UserId == request.UserId);
 
-            if (request.Name is not null)
+            if (!string.IsNullOrEmpty(request.Name))
             {
                 var normalizedName = request.Name.Trim().ToUpperInvariant();
                 playListsQuery = playListsQuery.Where(p => p.NormalizedName.Contains(normalizedName));

backend/Musify.Application/Tracks/GetTracks.cs

@@ -24,7 +24,7 @@ namespace Musify.Application.Tracks
                 .Include(ut => ut.Track)
                 .AsQueryable();
 
-            if (request.Name is not null)
+            if (!string.IsNullOrEmpty(request.Name))
             {
                 var normalizedName = request.Name.Trim().ToUpperInvariant();
                 tracksQuery = tracksQuery.Where(t => t.Track.NormalizedTitle.Contains(normalizedName));

backend/Musify.Application/Tracks/GetTracksByUserId.cs

@@ -28,7 +28,7 @@ namespace Musify.Application.Tracks
                 .Include(ut => ut.Track)
                 .Where(p => p.UserId == request.UserId);
 
-            if (request.Name is not null)
+            if (!string.IsNullOrEmpty(request.Name))
             {
                 var normalizedName = request.Name.Trim().ToUpperInvariant();
                 tracksQuery = tracksQuery.Where(t => t.Track.NormalizedTitle.Contains(normalizedName));

backend/Musify.Application/Users/GetUsers.cs

@@ -20,7 +20,7 @@ namespace Musify.Application.Users
                 .AsNoTracking()
                 .AsQueryable();
 
-            if (request.UsernameSearch is not null)
+            if (!string.IsNullOrEmpty(request.UsernameSearch))
             {
                 var normalizedUsername = request.UsernameSearch.Trim().ToUpperInvariant();
                 user = user.Where(u => u.NormalizedName.Contains(normalizedUsername));